The present invention relates generally to chemical spraying systems and more specifically to a chemical loading system.
Eductors are often used to transfer chemical concentrate from a container to a main solution tank on an implement such as an agricultural sprayer. Most conventional eductors are bulky and heavy and require much mounting space and a hefty lift structure for movement between a loading position convenient for operator access and an out of the way storage position for spray and transport operations. Many currently available eductors do not have closed transfer technology capabilities and therefore are limited in use. In addition, loading liquid chemical is often a slow process using an eductor. In most conventional systems, a venturi is located at the bottom of a hopper or at a location in the vacuum line such that there is a considerable mass of material to lift. Such arrangements adversely affect venturi efficiency and increase loading time.
Loading the dry chemical through the tank lid is not only slow but also a very labor intensive process. However, loading dry chemical with an eductor is also very slow, and bridging of dry material at the bottom of the hopper is a common problem. Since granular materials can have considerable air space, the venturi created vacuum often does not effectively draw the dry material.
The hopper area needs to be thoroughly cleaned between loading of different chemicals, and presently available systems have shapes that are difficult to rinse and require special plumbing arrangements for rinse water. The rinsing arrangements often do not reach all areas of the hopper walls.
It is therefore an object of the present invention to provide an improved chemical loading system for a solution tank on an agricultural sprayer or similar implement. It is a further object to provide such a system which overcomes most or all of the aforementioned problems.
It is another object of the present invention to provide an improved chemical loading system for a solution tank which is lighter and requires less space than most previously available loading systems. It is another object to provide such a system which is easier to move between operating and storage positions.
It is a further object to provide such a system which loads faster and is more convenient to access than most previously available loading systems and reduces the chemical handling time of the operator. It is another object to provide such a system which has an improved hopper flow path and venturi location.
It is another object of the present invention to provide a chemical loading system with faster loading, improved clean-out and an improved rinse structure.
It is yet another object to provide an improved chemical loading system which facilitates closed transfer and closed clean-out operations.
It is a further object of the invention to provide an improved chemical loading system which effectively loads dry chemicals. It is another object to provide such a system which reduces air space in the dry chemicals thereby providing better material draw by the venturi. It is still another object to provide such a system which includes a combination of a rinse ring at the top of the hopper, an improved venturi location and an anti-bridging nozzle.
It is yet another object to provide an improved chemical loading system having a unique hopper construction which is compact and relatively inexpensive. It is still another object to provide such a system having a strategically located rinse ring which increases rigidity and directs rinse fluid to all areas of the hopper for improved hopper cleaning. It is a further object to provide such a structure wherein the rinse ring forms a smooth upper hopper edge portion.
The chemical loading system or eductor includes a venturi located at the top of the solution tank to significantly improve performance by reducing the time to load chemicals. Compared to a venturi at the bottom of the hopper or elsewhere in the vacuum line, the top of the tank venturi location reduces the fluid mass that has to be lifted into the tank, therefore increasing the venturi efficiency. The eductor decreases the load time by increasing the flow rate of the venturi by placing it at the top of the tank and adding an anti-bridging nozzle at the outlet of the eductor hopper. The nozzle ensures that material is pushed into the vacuum created by the venturi.
To reduce air space in the granular material and increase pull by the venturi vacuum, fluid is directed to the material through the nozzle and through a rinse ring around the top of the hopper. The fluid and granular mixture, without air spaces, can be pulled by the venturi very efficiently. The rinse ring, also used to rinse the hopper after loading the material, includes a rolled edge at the top of the hopper walls with notches in the edge of the ring to provide improved placement of the rinsing solution. The rolled edge defines the rinse tube, a smooth protective edge upper, and structural rigidity to the lightweight hopper. By forming the rinse ring in a single process, material and manufacturing costs are reduced while providing the above-mentioned features.
The lighter weight and more compact hopper design reduces the need for a spring assist lift linkage, therefore also reducing cost and complexity. The hopper capacity is preferably on the order of 5.5 U.S. gallons while some current designs are approximately 6.5 gallons. The shape of the improved eductor opens space up on the sprayer for other options. A sleek bottom shape on the eductor is pleasing to the eye, compact and smooth so that easy clean-out and an easy flow path for a non-splash pour of chemicals are provided. The eductor also includes a flat accessible lid for the mounting of connections to be used with chemical containers for the use of closed transfer technology.